Datastage Interview Question and Answers
| 6. |
What is a merge? |
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- Merge is a stage that is available in both parallel and server jobs.
- The merge stage is used to join two tables(server/parallel) or two tables/datasets(parallel).
- Merge requires that the master table/dataset and the update table/dataset to be sorted.
- Merge is performed on a key field, and the key field is mandatory in the master and update dataset/table.
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| 7. |
What are Sequencers? |
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A sequencer allows you to synchronize the control flow of multiple activities in a job sequence. It can have multiple input triggers as well as multiple output triggers. |
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| 8. |
What is version Control? |
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Version Control stores different versions of DS jobs runs different versions of same job reverts to previos version of a job view version histories. |
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| 9. |
What is Active and Passive Stage? |
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Passive Stages are used for data extraction and loading ,while Active Stage are used to implements and process the business rules. |
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| 10. |
What are the main features of datastage? |
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DataStage has the following features to aid the design and processing required to
build a data warehouse : - Uses graphical design tools. With simple point and click techniques you
can draw a scheme to represent your processing requirements.
- Extracts data from any number or types of database.
- Handles all the metadata definitions required to define your data warehouse. You can view and modify the table definitions at any point during
the design of your application.
- Aggregates data. You can modify SQL SELECT statements used to extract
data.
- Transforms data. DataStage has a set of predefined transforms and functions
you can use to convert your data. You can easily extend the
functionality by defining your own transforms to use.
- Loads the data warehouse.
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Gk Questions with Answers